* syncase.scm: Set expansion-eval-closure to

* syncase.scm: Set expansion-eval-closure to
the-syncase-eval-closure during booting so that variables are
created in the correct module;
(define-syntax define-syntax-public eval-when fluid-let-syntax
identifier-syntax let-syntax letrec-syntax syntax syntax-case
syntax-rules with-syntax include): Removed definitions (these are
created from within psyntax.pp).